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Fix 11124: FP knownConditionTrueFalse with fruit (#4196) 

* Update valueType

* Allow comparisons

* Fix compare op

* Add test

* Format

* Fix FP

* Format
This commit is contained in:
Paul Fultz II 2022-06-11 04:02:04 -05:00 committed by GitHub
parent 8579feb3aa
commit 8945c151f5
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2 changed files with 57 additions and 7 deletions
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38
lib/programmemory.cpp
View File

@ -548,6 +548,11 @@ struct assign {
}
};
static bool isIntegralValue(const ValueFlow::Value& value)
{
return value.isIntValue() || value.isIteratorValue() || value.isSymbolicValue();
}
static ValueFlow::Value evaluate(const std::string& op, const ValueFlow::Value& lhs, const ValueFlow::Value& rhs)
{
ValueFlow::Value result;
@ -569,14 +574,33 @@ static ValueFlow::Value evaluate(const std::string& op, const ValueFlow::Value&
return result;
}
}
result.valueType = ValueFlow::Value::ValueType::INT;
if (op == "+") {
if (lhs.isIteratorValue())
result.valueType = lhs.valueType;
else if (rhs.isIteratorValue())
result.valueType = rhs.valueType;
} else if (lhs.valueType != rhs.valueType) {
// Must be integral types
if (!isIntegralValue(lhs) && !isIntegralValue(rhs))
return ValueFlow::Value::unknown();
// If not the same type then one must be int
if (lhs.valueType != rhs.valueType && !lhs.isIntValue() && !rhs.isIntValue())
return ValueFlow::Value::unknown();
bool compareOp = contains({"==", "!=", "<", ">", ">=", "<="}, op);
// Comparison must be the same type
if (compareOp && lhs.valueType != rhs.valueType)
return ValueFlow::Value::unknown();
// Only add, subtract, and compare for non-integers
if (!compareOp && !contains({"+", "-"}, op) && !lhs.isIntValue() && !rhs.isIntValue())
return ValueFlow::Value::unknown();
// Both cant be iterators for non-compare
if (!compareOp && lhs.isIteratorValue() && rhs.isIteratorValue())
return ValueFlow::Value::unknown();
// Symbolic values must be in the same ring
if (lhs.isSymbolicValue() && rhs.isSymbolicValue() && lhs.tokvalue != rhs.tokvalue)
return ValueFlow::Value::unknown();
if (!lhs.isIntValue() && !compareOp) {
result.valueType = lhs.valueType;
result.tokvalue = lhs.tokvalue;
} else if (!rhs.isIntValue() && !compareOp) {
result.valueType = rhs.valueType;
result.tokvalue = rhs.tokvalue;
} else {
result.valueType = ValueFlow::Value::ValueType::INT;
}
bool error = false;
result.intvalue = calculate(op, lhs.intvalue, rhs.intvalue, &error);

26
test/testcondition.cpp
View File

@ -4364,6 +4364,32 @@ private:
" return 0;\n"
"}\n");
ASSERT_EQUALS("[test.cpp:2] -> [test.cpp:2]: (style) Condition 'b' is always false\n", errout.str());
// #11124
check("struct Basket {\n"
" std::vector<int> getApples() const;\n"
" std::vector<int> getBananas() const; \n"
"};\n"
"int getFruit(const Basket & b, bool preferApples)\n"
"{\n"
" std::vector<int> apples = b.getApples();\n"
" int apple = apples.empty() ? -1 : apples.front();\n"
" std::vector<int> bananas = b.getBananas();\n"
" int banana = bananas.empty() ? -1 : bananas.front();\n"
" int fruit = std::max(apple, banana);\n"
" if (fruit == -1)\n"
" return fruit;\n"
" if (std::min(apple, banana) != -1)\n"
" fruit = preferApples ? apple : banana;\n"
" return fruit;\n"
"}\n");
ASSERT_EQUALS("", errout.str());
check("void f(const std::string & s, int i) {\n"
" const char c = s[i];\n"
" if (!std::isalnum(c)) {}\n"
"}\n");
ASSERT_EQUALS("", errout.str());
}
void alwaysTrueInfer() {